Bay Weekly: Earth Journal

The Crow

The crows above the forest call;
Tomorrow they may form and go.
Oh, hushed October morning mild,
Begin the hours of this day slow.
—Robert Frost

The crow circled over a field of corn stubble, preparing to land. The field was next to the road; I sat at the stop sign and watched. Instead of making a direct approach, the crow made loops and circles in the air like an artist signing his name before gliding down 15 to 20 feet for an easy landing.

I am no student of aerodynamics, so I can’t say the bird was instinctively adapting its approach to slight breeze. To my eyes, it was having fun, enjoying its enviable ability. And why not?

Crows belong to a family — including ravens, jays and magpies — called corvids. Corvids are considered the most intelligent birds. “It appears that no other birds approach their breadth of intelligence,” wrote artist and author Tony Angell.

All birds, all wild animals, possess finely honed survival skills, but among birds only corvids and perhaps parrots seem to have intellectual ability that goes beyond instinct.

Evidence of their intelligence includes their sense of fun, a capacity many have observed. Additionally, corvids are reported to have a higher brain-to-body-size ratio than any other family of bird. In laboratory’s they have revealed advanced learning abilities, including tool use.

Corvids are also very social, and some species are known for altruistic tendencies, which are believed to increase survivability. The American crow uses at least 23 different vocalizations to communicate a variety of messages such as assembly, dispersal, scolding and contentment.

Chesapeake Country is home to two species of crow. The American crow and the slightly smaller fish crow are almost identical. It’s difficult to differentiate them by size because of the great variability among birds. Fish crows are found near marshes and rivers and often mix with their American cousins; the distinctive nasal quality of their vocalizations is how birders identify them.

The mosquito-borne West Nile virus affects many forms of life including humans and horses, but especially birds. The virus is deadly to corvids and, in particular, crows.

News reports from past summers made it seem as if dead crows littered the landscape. The extent to which West Nile will affect bird populations is not well understood, but scientists believe the virus could potentially devastate many bird species. Will such a tragedy occur? If it does, will bird population eventually rebound? The answers are elusive.

A doctor friend notes that viruses are very smart: They adapt well, and they are hard to control. Those characteristics remind me of crows. Viruses are formidable adversaries, and that is bad news for crows.